Abstract: This invention provides a DNA sequence coding for a cleavage site which is specifically cleaved by blood coagulation Factor Xa, a vector containing such a sequence, and a host organism transformed with such a vector. Preferably, in the vector, the Factor Xa cleavage site coding sequence is fused at one end to a product and at its other end to an ATG codon or a sequence coding for at least part of a host protein.This invention also provides a process, for the production of a desired protein or peptide product in native form, comprising:transforming a host organism with a vector as described above;expressing the desired protein or peptide product as a fusion protein comprising the desired protein or peptide product fused to a Factor Xa cleavage site; anda cleaving the fusion protein with Factor Xa to yield the foreign gene product in native form.

Abstract: A novel, generally applicable method for producing correctly folded proteins from a mixture of misfolded proteins, e.g. bacterial inclusion-body aggregates. A major new aspect of the method is that over-all efficiency is achieved by subjecting proteins to a time-sequence of multiple denaturation-renaturation cycles, resulting in gradual accumulation of the correctly folded protein. The method has proven efficient for a variety of recombinant proteins. Also provided are novel encrypted recognition sites for bovine coagulation factor X.sub.a. The encrypted recognition sites described may be activated in vitro by controlled oxidation or by reversible derivatization of cysteine residues and thereby generate new cleavage sites for factor X.sub.a. Two new recombinant serine protease exhibiting narrow substrate specificity for factor X.sub.a recognition sites are also provided. They may replace natural coagulation factor X.sub.a for cleavage of chimeric proteins.

Abstract: A novel, generally applicable method for producing correctly folded proteins from a mixture of misfolded proteins, e.g. bacterial inclusion-body aggregates. A major new aspect of the method is that over-all efficiency is achieved by subjecting proteins to a time-sequence of multiple denaturation-renaturation cycles, resulting in gradual accumulation of the correctly folded protein. The method has proven efficient for a variety of recombinant proteins. Also provided are novel encrypted recognition sites for bovine coagulation factor X.sub.a. The encrypted recognition sites described may be activated in vitro by controlled oxidation or by reversible derivatization of cysteine residues and thereby generate new cleavage sites for factor X.sub.a. Two new recombinant serine protease exhibiting narrow substrate specificity for factor X.sub.a recognition sites are also provided. They may replace natural coagulation factor X.sub.a for cleavage of chimeric proteins.